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Post by ammocarbsteve on Jun 14, 2013 1:42:26 GMT -5
I spotted this when my friend was over collecting recently... I know its only a bit of old wood but its the best bit of old wood I have seen on the Somerset coast so I collected it rather than it get eroded away by the sea...It looks much more 3D than usual and it also looks like it has been burnt lol...or just the dark preservation?... Attachments:
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Post by ammocarbsteve on Jun 14, 2013 1:43:16 GMT -5
Cont... Attachments:
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Post by ammocarbsteve on Jun 14, 2013 1:44:41 GMT -5
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Post by Joe Botting on Jun 14, 2013 2:54:47 GMT -5
Wow, Steve - that is a really, really nice find. I'm sure you're right that it's firewood, too: burning wood makes it much more stable by transforming the decay-able molecules into effectively pure carbon. As a result, you can end up with exquisite preservation of cell structures and the like. The cracking and so forth looks exactly like the effects of fire, and I'm sure it's been through a forest fire. There's been a lot of work on these things in recent years, especially for the Carboniferous (when there were very high oxygen levels, so fires caught very easily). It seems the reasons are debated, though... see here for a good detailed read: www2.ju.edu.jo/sites/Academic/a.abuhamad/Lists/Published%20Research/Attachments/9/1.The%20record%20of%20Triassic%20charcoal%20.pdf |
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Post by ammocarbsteve on Jun 14, 2013 4:09:57 GMT -5
Joe.... Thanks.... I am glad i collected it....It was the preservation that attracted my attention really, much better than the usual fine carbon film I have seen previously...and now I know why !... Thanks for the link I shall have a read up on the subject.... Heres a couple more images... The specimen was still wet when I photographed it and it lost some of the detail I think... Attachments:
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Post by ammocarbsteve on Jun 14, 2013 4:11:15 GMT -5
Cont... Anyone ever researching Jurassic forest fires have some better images to consider.... Attachments:
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Post by ammocarbsteve on Jun 14, 2013 12:38:42 GMT -5
Joe.... I was given some advice regarding the possibility of this being firewood as in charred or burned and then undertook a small test... I was informed if it was charred or burned a small piece would produce a black line on paper but if it was coalified or partially coalified the trace would be brown... The mark was definately brown...
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Post by Joe Botting on Jun 14, 2013 15:16:29 GMT -5
Well... I could be wrong, of course. However, it does vary in colour quite a bit over the surface as well, and I'm guessing you took the bit that would break off most easily, at the right edge? If so, it seems to me that the cracking coincides mostly with a much darker area... perhaps it's partly burned? It might be worth trying the streak from some other parts of it.
The other thing is that I'm not convinced that the test takes into account pyrite grains that might have filled pore spaces, and weathered to oxides... you might be getting a streak partly from the rust instead?
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Post by ammocarbsteve on Jun 15, 2013 1:21:54 GMT -5
Joe.... Samples... Yes...The right edge and also where it fragments entering the rock at top left in the photo...
Partly burned is a distinct possibility... The cracking you have pointed out and also the 'rounding off' of the edges and of course the colour variations...all indicators that it could of been exposed to fire at some point but perhaps not fully charred...My friend even said it looked burned when I pointed it out on the day...
Pyrite ?... the wood is rather stronger/harder than I imagined...
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Post by ammocarbsteve on Jun 15, 2013 3:49:43 GMT -5
PS... just a thought,driftwood also gets rounded off...
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Post by reighan on Jun 16, 2013 4:05:51 GMT -5
You find the nicest things... I probably wouldn't run across these discussions in a textbook either. :-)
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Post by ammocarbsteve on Jun 19, 2013 1:49:26 GMT -5
reighan.... You might... reading Joes link, forest fires is pretty 'paleo-fashionable' textbooks of the nr future....
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Post by reighan on Jun 19, 2013 14:52:28 GMT -5
:-)
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Post by pleecan (Peter Lee) on Jun 22, 2013 10:28:23 GMT -5
Super find Steve!!! Congratulations!
PL
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